Rail head clamp



May 17, 1955 s. H. CLARK v RAIL HEAD CLAMP Filed June 26, 1952 FIEL I3.

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United States Patent O RAIL HEAD CLAMP Stanley H. Clark, Provo, Utah,assignor to United States `Y The present invention relates to clampingdevices and clamp which is particularly suited for detachably mountingsignals and the like on railroad rail heads of various sizes.

The nature of the invention and its distinguishing 2,708,557 PatentedMay 17, 195.5

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wardly to the position shown in Figure 1 to cause clamp arm 12 to moverelative to the clamp arm 2 to achieve engagement of the rail head W byjaw 16 opposite jawr 10. Movement of the actuating arm in this directioncauses stretching of the spring 26 which in turn pulls the upper end ofthe movable clamp arm 12 to move the jaw 16 into positive engagementwith the rail head. When the jaws 16 and 10 engage the rail head, thebifurcated end 32 of the actuating arm engages the rounded projection 13of the movable clamp arm, and

. the transverse wall 36 abuts the outer surface of lthe features andadvantages will be fully apparent from the following detailed disclosureand the appended claims when read in connection with the accompanyingdrawings in which:

Figure l is an elevational view showing the clamp of my invention inclamping engagement with a rail head;

Figure 2 is a view similar to Figure lshowing the clamp in opennon-clamping position; and

Figure 3 is a plan view of Figure 2.

Referring more particularly to the drawings, reference numeral 2indicates a relatively stationary clamp arm having an angularly bentportion 4 at its lower end and a warning signal 6 axed to its upper endby means of bolts or rivets 8. The bent end portion 4 of the clamp arm 2has a channel shaped jaw 10 laterally disposed thereon adjacent its end.The jaw 10 is shaped to engage a rail head W, as shown in Figure l, andhas an opening suitably shaped for this purpose which faces toward aprojection of the longitudinal axis of the straight portion of the clamparm 2. A movable clamp arm 12 which is somewhat shorter than thestationary clamp arm 2 is pivotally mounted intermediate its ends ontothe clamp 2, as at 14, adjacent the junction of the straight and bentportions of the stationary clamp arm. The lower end of the movable clamparm 12 is provided with a rail head-engaging jaw 16 which matches thejaw 10 and is positioned adjacent thereto with its opening facing theopening of jaw 10. A rounded projection 18 having a hole 20 therethroughis provided on the end of the movable clamp arm 12 adjacent to the jaw16.

An actuating arm 22 which is substantially L-shaped in form is pivotallyattached by its one end 24 to the clamp arm 2 intermediate the pivotalmounting 14 of the clamp arm 12 and the signal-bearing end of the clamparm 2. A helical tension spring 26, having closely spaced convolutions,extends between and is connected at one end to an anchor post 28projecting from the surface of the clamp arm 12 adjacent its upper end.The spring 26 is connected by its other end to an anchor post 30projecting from the surface of the actuating arm 22 adjacent its end 24.The opposite end 32 of the actuating arm 22 is bifurcated and isprovided with a hole 34 extending transversely through the bifurcations.A transverse wall 36 is provided between the bifurcations adjacent thebases thereof.

A projecting handle member 3S is aixed to the actuating arm tofacilitate its manipulation, and a stop member is provided on thesurface of the actuating arm opposite the handle 3S to restrict therotation of the arm past the clamp arm 2.

In operation, the jaw 10 is alrxed to the rail head W, and the end 32 ofthe actuating arm 22 is moved downrounded projection 18 to preventfurther movement. of the actuating arm toward the jaw 16. In thisposition, the holes 20 and 34 are in alignment so that a lock may f beinserted therethrough to secure the4 clamp and prevent hasn for itsgeneral object the providing of an improved its removal by unauthorizedpersonnel. y .l

In order to provide positive locking actionon the part of the actuatingarm when its end is moved toward the jaw 16, the spring 26 must be sopositioned that its axis is below the axis of the pivotal mounting ofthe actuating arm when the jaws 16 and 10 are in engagementv with therail head. This arrangement eliminates the need of any other holdingmeans to maintain the actuating arm in position when the jaws are inclamping engagement with the rail head. Positioning the spring in thismanner creates a continuing force urging the upper end of the movableclamp 12 toward the pivotal connection of the actuating arm 22. At thesame time, the actuating arm is prevented from moving further towardsthe jaws by means of its abutting engagement with the rounded projection1S as described above and shown in Figure l. Thus, all the forces aredirected to holding the jaws in tight engagement with the rail head whenthe actuating arm is pulled downwardly in operating position.

When it is desired to remove the clamp from the rail head, the handle 3Sis grasped and the actuating arm 22 is moved upwardly to the positionshown in Figure 2. This movement reduces the tension of the spring andmoves the axis of the spring 26 above the pivotal connection of theactuating arm. As the arm 22 is rotated toward the limit of its upwardmovement, the upper end of the movable clamp 12 is caused to movedownwardly to the position shown in Figure 2. This movement obviouslycauses the jaw 16 to move away from the rail head W thus freeing theclamp from engaging position.

It will be noted that the device of my invention may be clamped onvarious sized railroad rails without adjustment by virtue of the springtension arrangement incorporated therein. This feature permits universaluse t of the device on railroad tracks as well as specially sizedequipment tracks such as mine tracks, etc. In addition, the springtension feature assures positive clamping action at all times. In theevent of vibration or oscillation of the signal in strong wind, thedisturbance merely causes the clamp to grip more and more securely.

It is not intended to limit the scope of this invention to the usethereof for holding warning signals on rail road tracks, but rather toinclude any uses to which the invention lends itself and to anymodification of the invention within the scope of the claims hereinafterstated.

I claim:

l. A clamping device for detachably mounting an object on a rail headand the like which comprises a relatively long clamp arm, a railhead-engaging jaw adjacent one end of said arm, means for supportingsaid object at the other end of said arm, a short clamp arm pivotallymounted intermediate its ends on said long clamp arm, a railhead-engaging jaw on one end of said short clamp arm adjacent the jaw onsaid long clamp arm, an actuating arm pivotally mounted by one end tosaid long clamp arm at a point intermediate the pivotal mounting of saidshort clamp arm and the object supporting end of said long clamp arm,and a helical spring having closely spaced convolutions extendingbetween and connected to said actuating arm and said short clamp arm andadapted to move said short clamp arm relative to said long clamp armwhen said actuating arm is moved, means for restricting the movement ofsaid actuating arm toward said jaws. Y

2. A'clamping device as defined in claim l characterized'by the axis ofsaid spring being between the axis ofthe pivotal mounting of saidactuatingarm and the axis of` the pivotal mounting of said short clamparm when the jaws are in engagement with said rail head.

3. A clamping device for detachably mounting an object on a rail headand the like which comprises a relatively stationary clamp arm, anangularly .bent portion at one end of said arm, means for supportingsaid object at the opposite end of said arm, a channel shaped railhead-engaging jaw laterally disposed in said bent end portion normalthereto with the opening of said jaw facing toward a projection of thelongitudinal axis of the straight portion of said arm, a movable clampjaw pivotally mounted intermediate its ends on said stationary clamp armat a point adjacent said bent end portion, a channel shaped railhead-engaging jaw laterally disposed adjacent one end of said movableclamp arm and normal thereto adjacent the jaw on said stationary clamparm with the opening of said jaws facing each other, a roundedprojection having a hole therethrough on the end of said movable clamparm adjacent the jaw thereon, an actuating arm pivotally mounted by oneend to said stationary clamp arm at a point intermediate the pivotalmounting of saidmovableclamp arm and the object supporting end of saidstationary clamp arm, the end of said actuating Varm opposite vitspivotal mounting being bifurcated and having a transverse holetherethrough, a transverse wall between said bifurcations adjacent thebases thereof, and a helical spring having closely spaced convolutionsextending between and connected to said actuating arm and said movableclamp arm and adapted to move said short clamp relative to saidstationary clamp arm when said actuating arm is moved,ksaid bifurcatedend of said actuating arm being engaged with the rounded projection ofsaid movable .clamp arm with said transverse wall abutting saidprojection and the hole through said bifurcated end being in alignmentwith the hole through said rounded projection when said jaws are inengagement with said rail head.

4. A clamping device as defined in claim 3 characterized by the axis ofsaid spring being between the axis of the pivotal mounting of saidactuating arm and the axis of the pivotal mounting of said movable clamparm when the jaws are in engagement with said rail head.

5. A clamping device as defined in claim 4 including.

a stop member attached to and projecting from the surface Of saidactuating arm and adapted to engage the edge of said stationary clamparm to limit the movement of said actuating arm when said jaws are movedaway from each other.

6. A clamping device as dened in claim 5 characterized by an elongatedhandle member being attached to and projecting normal to the surface ofsaid actuating arm for manipulating the same.

ReferencesiCited in the tile of this patent UNITED STATES PATENTS

